SQLSERVER 表分区操作和设计方法,需要的朋友可以参考下。
一 .聚集索引
聚集索引的页级别包含了索引键,还包含数据页,因此,关于 除了键值以外聚集索引的叶级别还存放了什么的答案就是一切,也就是说,每行的所有字段都在叶级别种。
另一种说话是:数据本身也是聚集索引的一部分,聚集索引基于键值保持表中的数据有序。
SQL SERVER 中,所有的聚集索引都是唯一的,
二 .非聚集索引
对于非聚集索引,叶级别不包含全部的数据。除了键值以外,每个叶级别(树的最低层)中的索引行包含了一个书签(bookmark),告诉SQL Server 可以在哪里找到与索引键相应的数据行。一个书签课能有两种格式。如果表上存在聚集索引,书签就是相应的数据行的聚集索引键。如果表是堆(heap)结构 ,就是没有聚集索引的情况下 ,书签就是一个行标识符 row identifier,rid ,以 文件号 页号 槽号 的格式来定位实际的行。
三 .包含索引
索引键字段数量限制是16个,总共900个字节大小 ,包含性列只在叶级别中出现而且不以任何方式控制索引行的排序。这可能发生在索引建立于分区表 也就是我今天是发的博客 O(∩_∩)O (partitioned table )上没有指定 on filegroup 或者 no partition_scheme 的情况下。
一 .SQL SERVER 表分区介绍:
SQL Server 引入的表分区技术,让用户能够把数据分散存放到不同的物理磁盘中,提高这些磁盘的并行处理性能以优化查询性能……
二 .SQL SERVER 数据库表分区由三个步骤来完成:
1.创建分区函数
2.创建分区架构
3.对表进行分区
基于缓存更新机制,我使用时间来进行分区,这里大家根据业务的要求使用合适的字段来作为分区
创建数据库分区文件数量,这里存储一年的数据分成十二个分区,需要现在D盘建立好Data 的文件夹 里面包含Primary 文件夹和 FG1 FG2 FG3 FG4............
代码如下:
IF EXISTS (SELECT name FROM sys.databases WHERE name = N'AirAvCache')
DROP DATABASE [AirAvCache]
GO
CREATE DATABASE [AirAvCache]
ON PRIMARY
(NAME='Data Partition DB Primary FG',
FILENAME=
'D:\Data\Primary\AirAvCache Primary FG.mdf',
SIZE=5,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG1]
(NAME = 'AirAvCache FG1',
FILENAME =
'D:\Data\FG1\AirAvCache FG1.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG2]
(NAME = 'AirAvCache FG2',
FILENAME =
'D:\Data\FG2\AirAvCache FG2.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG3]
(NAME = 'AirAvCache FG3',
FILENAME =
'D:\Data\FG3\AirAvCache FG3.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG4]
(NAME = 'AirAvCache FG4',
FILENAME =
'D:\Data\FG4\AirAvCache FG4.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG5]
(NAME = 'AirAvCache FG5',
FILENAME =
'D:\Data\FG5\AirAvCache FG5.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG6]
(NAME = 'AirAvCache FG6',
FILENAME =
'D:\Data\FG6\AirAvCache FG6.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG7]
(NAME = 'AirAvCache FG7',
FILENAME =
'D:\Data\FG7\AirAvCache FG7.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG8]
(NAME = 'AirAvCache FG8',
FILENAME =
'D:\Data\FG8\AirAvCache FG8.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG9]
(NAME = 'AirAvCache FG9',
FILENAME =
'D:\Data\FG9\AirAvCache FG9.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG10]
(NAME = 'AirAvCache FG10',
FILENAME =
'D:\Data\FG10\AirAvCache FG10.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG11]
(NAME = 'AirAvCache FG11',
FILENAME =
'D:\Data\FG11\AirAvCache FG11.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 ),
FILEGROUP [AirAvCache FG12]
(NAME = 'AirAvCache FG12',
FILENAME =
'D:\Data\FG12\AirAvCache FG12.ndf',
SIZE = 5MB,
MAXSIZE=500,
FILEGROWTH=1 )
创建好后如图:
打开FG1 文件夹 看到多了AirAvCacheFG1.ndf 文件
创建分区函数
代码
代码如下:
USE AirAvCache
GO
-- 创建函数
CREATE PARTITION FUNCTION [AirAvCache Partition Range](DATETIME)
AS RANGE LEFT FOR VALUES ('2010-09-01','2010-10-01','2010-11-01','2010-12-01','2011-01-01','2011-02-01','2011-03-01','2011-04-01','2011-05-01','2011-06-01','2010-07-01');
创建分区架构
代码
代码如下:
CREATE PARTITION SCHEME [AirAvCache Partition Scheme]
AS PARTITION [AirAvCache Partition Range]
TO ([AirAvCache FG1], [AirAvCache FG2], [AirAvCache FG3],[AirAvCache FG4],[AirAvCache FG5],[AirAvCache FG6],[AirAvCache FG7],[AirAvCache FG8],
[AirAvCache FG9],[AirAvCache FG10],[AirAvCache FG11],[AirAvCache FG12]);
创建一个使用AirAvCache Partitiion Scheme 架构的表
代码如下:
CREATE TABLE [dbo].[AvCache](
[CityPair] [varchar](6) NOT NULL,
[FlightNo] [varchar](10) NULL,
[FlightDate] [datetime] NOT NULL,
[CacheTime] [datetime] NOT NULL DEFAULT (getdate()),
[AVNote] [varchar](300) NULL
) ON [AirAvCache Partition Scheme] (FlightDate); --注意这里使用[AirAvCache Partition Scheme]架构,根据FlightDate 分区
查询分区情况
代码如下:
-- 查看使用情况
SELECT *, $PARTITION.[AirAvCache Partition Range](FlightDate)
FROM dbo.AVCache
可以看到9 月和 10 月已经分开了。

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